How Many Litters Can a Dog Have in a Lifetime?

Female dogs go into heat every six months from the onset of their first heat. The gestation period is approximately 63 days, with an additional six weeks of nursing the puppies. Theoretically, a dog can give birth three times per year over its lifetime, but this puts tremendous strain on its body. Professional breeders generally breed their dogs twice in the animal's lifetime between the ages of 6 and 8 years.